Gadget Download

Nowadays there are various electronic equipments available for remote operation of electronic devices. But, the main disadvantage of these systems is that they can be operated only in short ranges and also less reliable. Thus, to overcome the above drawbacks, we are using one of the wireless communication technique i.e., GSM.

           GSM(Global Systems for Mobile Communication) is vastly used because of its simplicity in both transmitter and receiver design, can operate at 900 or 1800MHZ band, faster, more reliable and globally network. Here the system is capable of controlling the motor by receiving control messages from an authorized mobile number. Microcontroller is the heart of our system, which controls the overall operation of our system. System always alert for receiving SMS  from valid number then that particular messages are displayed on our LCD(Liquid Crystal Display) i.e., whether the motor should rotate in right shift or left shift with a speed of so and so.

We are using H-Bridge as an driver for our DC Motor because our Microcontroller cannot provide the maximum current to drive a DC Motor. GSM network operators have roaming facilities, user can often continue to use there mobile phones when they travel to other countries etc. In contrast, a microcontroller not only accepts the data as inputs but also manipulates it, interfaces the data with various devices, controls the data and thus finally gives the result.

This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.

Notice Board is primary thing in any institution / organization or public utility places like bus stations, railway stations and parks. But sticking various notices day-to-day is a difficult process. A separate person is required to take care of this notices display. This project deals about an advanced hi-tech wireless notice board.

Matrix type display is designed using 5mm LED on a printed circuit board. A driver circuit is designed to drive all these LEDs. A GSM/CDMA Mobile Can is used to enter the required text or notice. The scrolling speed of the text also can be changed according to user requirement.

                                

After entering the text the SMS is sent to the no which is connected to the LED display. At any time the user can add or remove or alter the text according to his requirement.

At the receiving end the GSM modem which is connected to the Max 232 receives the message and is connected to the microcontroller AT89S52. The message which is already stored in the EEPROM is displayed on the LED Display.     

This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.